Azo dyestuff.



"UNIT D STATES PATENT OFFICE.

'osoAR GI'TNTHER' AND LEOPOLDY HESSE, OF ELnEnFEL-n, AND' ARTHUR .ZAR'I', 0F VOHWINKEL, GERMANY, ASSIGNORS T0 FARBENFABRIKEN VORM. FRIEDR. BAYER & 00., or ELBERFELD, eERMANxA CORPORATION or GERMANY.

AZO DYESTUFF.

No Drawing.

To all whom it may concern:

Be it known that we, Oscar: Giix'rnna and LEOPOLD Hesse, residing at Elberfeld, and ARTHUR ZART, residing at Vohwinkel, Germany. doctors of philosophy. chemists, citizens of the German Empire. lime invented a New Dye, of which the following is a specification.

Our invention relates to the preparation of new azo dyestutl's which are obtained by combining the diazo compound of QA-dinitrauilin with sulit'onic acids of aryl-hetanaphthylainins.

The formation of the new body is prob-.

' ahly best illustrated by the followii equation:

NIH: NzzN-OH l-uol }---NO2 l \l/ I N0 Nlh 2.1 dinitranilin. Diazo compound of 2.4. dinltranilin. Z1115).

-No, iNH.CH

to falling and to light, distinguished by their good resistance to the action of boiling mineral acids. v

In order to illustrate the new process more fully we can proceed as follows, the parts Specification of Letters Patent.

Application filed September 20, 1910. Serial No. 582,822.

heing hy weight :1 83 parts of QA-dinitrairil in are diazotized according to the method of diazotation described in British Letters Patent No. (3107/1894 with nitrosyl-sulfuric acid. The diazo compound is diluted with ice and added at about 0 C.to a suspension of 321 parts of the sodium salt of beta-phenylnaphthylamin-6-sulfonic acid of the formula un cane The combination is complete after a short time, but the stirring of the mixture is continued for some hours. The dye is then filtered oil' and dried. it is a bluish-black powder soluble in concentrated sulfuric acid with a red color; yielding'upon reduction with stannous chlorid and hydrochloric acid 1.2.4-triaminobenzene and 1-amin0-2-phenylaminonaphthalene-G-sulfonic acid. It dyes wool from acid baths a black.

Instead of phenyl-beta-naphthylamin-G- Patented Apr. 11,1911.

sult'onic acid other sulfonic acids 1'. g. 5- or 7-sulton1cor 5.7- or 6.8-d1sulfon1c acid or Slll'fOIllC acids of other aryl compounds such as the corresponding tolylor xylyl compounds, etc, may be used. From the 2-phev nylnapthylamin-8-sulfonic acid a brown dye is obtained.

Sulfonic acids of aryl-beta-naphthylamins which contain the sulfonic group in the aryl radical e. 1 the betaphenylnaphthylamin sulfonic acid W so.n

amino-beta-arylnaphthylamin; dyeing wool from acid baths level brown to black shades distinguished by their good resistance to the action of boiling mineral acids, substantially as described.

'2. The herein-described new azo dyestufi' obtainable'by reacting with diazotized 2.4:- dinitranilin upon beta-phenylnaphthylamin- 6-sulfonic acid, which dye is after being dried and pulverized in the shape of its sodium salt a bluish-black powder soluble in concentrated sulfuric acid With a red color; yielding upon reduction with stannous chlorid and hydrochloric acid 1.2.4-triaminobenzene and 1-amino-2-Phenylaminonaphthalene-6-sulf0nic acid; dyeing wool from acid 5 baths black, substantially as described.

In testimony whereof We have hereunto set our hands in the presence of two subscribing witnesses.

Vitnesses CHAS. J. WRIGHT, ALFRED HENKEL. 

